The video shows a prototype of a machine that is powered by the wind that reaches speeds higher than the wind, moving directly down wind.
DDWFTTW stands for Direct Down Wind Faster Than The Wind.
Every Windsurfer with a little bit of experience knows that this is impossible using just a stationary sail, because of losses due to friction, it is not even possible to go as fast as the wind, when moving directly down-wind. If you have an angle, it is possible to go faster than the wind using a modern sail.
Now how does this work? What you have to notice is that the turbine is not moving the wheels, but the wheels are moving the turbine, this means that the turbine is blowing in the direction that the wind is coming from. The wind pushes the cart forward, this sets the wheels in motion, which in turn sets the turbine in motion, which generates extra trust. Really cool and at first contra-intuitive. Don’t you just love engineering!!
This new-found knowledge will certainly buy you a beer at the bar, if you can lure the right people into a wager.